Information recording disc, recording and / or reproducing device and method

ABSTRACT

Four ECC blocks are recorded in a burst cutting area of an optical disc. Each ECC block is constituted by a BCA content code of 1 byte, content data length of 1 byte, and content data of 14 bytes. Of the BCA content data, the leading 6 bits are used for application ID and the remaining 2 bits are used for block number. Disc ID is stored in the content data. Since the four ECC blocks exist, the optical disc can be managed individually by four applications at the maximum. Thus it becomes possible to manage the same optical disc by a plurality of applications.

TECHNICAL FIELD

[0001] This invention relates to an information recording device andmethod, an information reproducing device and method, a recordingmedium, a program, and a disc recording medium, and particularly to aninformation recording device and method which enables recording of aplurality of disc IDs, an information reproducing device and method, arecording medium, a program, and a disc recording medium.

[0002] This application claims priority of Japanese Patent ApplicationNo. 2002-017246, filed on Jan. 25, 2002, the entirety of which isincorporated by reference herein.

BACKGROUND ART

[0003] As a disc recording medium on which, for example, digital datasuch as a high-quality digital video signal is optically recorded, aplayback-only DVD (digital versatile disc or digital video disc) hasbeen broadly known. Moreover, as disc recording media which enablewriting once or rewriting by using the DVD format, a DVD-R(DVD-recordable), a DVD-RW (DVD-rewritable) and a DVD-RAM (DVD-randomaccess memory) are being popularized.

[0004] Furthermore, a next-generation optical disc is to becommercialized which can realize a large capacity of approximately morethan 23 gigabytes with a track pitch of 0.32 μm, a scanning density of0.12 μm/bit and a diameter of 120 mm, by using a combination of a bluelaser beam with a wavelength of 405 nm and an objective lens with NA of0.85. With respect to this next-generation optical disc, a recordinglayer is formed on a substrate, and a transparent cover layer with athickness of approximately 0.1 mm is formed on the recording layer. Thetransparent cover layer has an excellent optical characteristic and itis hard-coated so as to be scratch-proof, for example. The laser beam iscast onto the recording layer via the transparent cover layer having theabove-described thickness of 0.1 mm.

[0005] By reducing the thickness of the transparent cover layer, thespot diameter of the laser beam on the recording layer can be reduced.However, if the spot diameter is thus reduced, the optical disc becomesmore susceptible to a dust particle of a size which would not cause anyproblem when the spot diameter is large.

[0006] Therefore, in the case of recording data onto the next-generationoptical disc with a thin transparent cover layer, reinforcement of anerror correcting code is necessary. This also applies to a BCA (burstcutting area) on an optical disc where the disc ID is recorded, as wellas a data area where content data is recorded.

[0007] However, since only one disc ID can be recorded on theconventional optical disc, a single optical disc cannot be managed by aplurality of applications.

DISCLOSURE OF THE INVENTION

[0008] In view of the foregoing status of the art, it is an object ofthe present invention to enable management of a single disc recordingmedium by a plurality of applications.

[0009] A first information recording device according to the presentinvention comprises: acquisition means for acquiring auxiliaryinformation; blocking means for blocking the auxiliary informationacquired by the acquisition means to generate error correction blockswith a header added thereto, the header containing an identificationnumber and a block number to which the auxiliary informationcorresponds; and recording means for recording the plurality of errorcorrection blocks containing the auxiliary information having the headeradded thereto, which are generated by the blocking means, into a burstcutting area on a-disc recording medium.

[0010] When arranging the same auxiliary information in each of theplurality of error correction blocks, the blocking means may give thesame block number to the plurality of error correction blocks in whichthe same auxiliary information is arranged.

[0011] When arranging the auxiliary information over the plurality oferror correction blocks, the blocking means may use serial numbers asthe block numbers of the plurality of error correction block over whichthe auxiliary information is arranged.

[0012] The blocking means may cause the header to contain lengthinformation representing the length of the auxiliary information.

[0013] Moreover, the blocking means may cause the header to containlength information representing the length of the auxiliary information,and when arranging the auxiliary information over the plurality of errorcorrection blocks, the blocking means may describe the actual length ofthe auxiliary information as the length information of each of theplurality of error correction blocks over which the auxiliaryinformation is arranged.

[0014] Furthermore, the blocking means may cause the header to containlength information representing the length of the auxiliary information,and if the auxiliary information is shorter than a fixed-length datapart of the error correction blocks, the blocking means may describe thelength of the data part of the error correction blocks as the lengthinformation of the error correction blocks.

[0015] The information recording device may also comprise modulationmeans for modulating the error correction blocks generated by theblocking means; and the recording means may record the error correctionblocks modulated by the modulation means into the burst cutting area onthe disc recording medium.

[0016] The blocking means may use error correction blocks having anerror correcting code RS(m,n,k) as the error correction blocks.

[0017] The modulation means may modulate only a part of parities-havinga length of k−1.

[0018] The modulation means may modulate only parities of (k−1)/2, whichare a part of parities having a length of k−1.

[0019] The modulation means may 4/1-modulate the error correctionblocks.

[0020] A first information recording method according to the presentinvention comprises: an acquisition step of acquiring auxiliaryinformation; a blocking step of blocking the auxiliary informationacquired by the processing of the acquisition step to generate errorcorrection blocks with a header added thereto, the header containing anidentification number and a block number to which the auxiliaryinformation corresponds; and a recording step of recording the pluralityof error correction blocks containing the auxiliary information havingthe header added thereto, which are generated by the processing of theblocking step, into a burst cutting area on a disc recording medium.

[0021] A program on a first recording medium according to the presentinvention is adapted for an information recording device for recording,onto a disc recording medium having a data area for recording main dataand a burst cutting area for recording auxiliary information, theauxiliary information proper to the disc recording medium, the programcomprising: an acquisition step of acquiring the auxiliary information;a blocking step of blocking the auxiliary information acquired by theprocessing of the acquisition step to generate error correction blockswith a header added thereto, the header containing an identificationnumber and: a block number to which the auxiliary informationcorresponds; and a recording step of recording the plurality of errorcorrection blocks containing the auxiliary information having the headeradded thereto, which are generated by the processing of the blockingstep, into the burst cutting area on the disc recording medium.

[0022] A first program according to the present invention is executableby a computer which controls an information recording device forrecording, onto a disc recording medium having a data area for recordingmain data and a burst cutting area, auxiliary information proper to thedisc recording medium, the program comprising: an acquisition step ofacquiring the auxiliary information; a blocking step of blocking theauxiliary information acquired by the processing of the acquisition stepto generate error correction blocks with a header added thereto, theheader containing an identification number and a block number to whichthe auxiliary information corresponds; and a recording step of recordingthe plurality of error correction blocks containing the auxiliaryinformation having the header added thereto, which are generated by theprocessing of the blocking step, into the burst cutting area on the discrecording medium.

[0023] A disc recording medium according to the present invention hasauxiliary information proper to the disc recording medium recorded in aburst cutting area, the auxiliary information being blocked to generateerror-correction blocks with-a header added thereto, the headercontaining an identification number and a block number to which theauxiliary information corresponds.

[0024] A second information recording device according to the presentinvention comprises: first acquisition means for acquiring auxiliaryinformation proper to a disc recording medium recorded in a burstcutting area, the auxiliary information being blocked to generate errorcorrection blocks with a header added thereto, the header containing anidentification number and a block number; second acquisition means foracquiring main data; encryption means for encrypting the main dataacquired by the second acquisition means on the basis of the auxiliaryinformation acquired by the first acquisition means; modulation meansfor modulating the main data encrypted by the encryption means; andrecording means for recording the main data modulated by the modulationmeans into a data area on the disc recording medium.

[0025] Only a part of parities having a length of k−1 of the auxiliaryinformation may be encoded.

[0026] Only parities-of (k−1)/2, which are a part of parities having alength of k−1, of the auxiliary information may be encoded.

[0027] The error correcting code RS(m,n,k) may be RS(248, 216, 33).

[0028] A second information recording method according to the presentinvention comprises: a first acquisition step of acquiring auxiliaryinformation proper to a disc recording medium recorded in a burstcutting area, the auxiliary information being blocked to generate errorcorrection blocks with a header added thereto, the header containing anidentification number and a block number; a second acquisition step ofacquiring main data; an encryption step of encrypting the main dataacquired by the processing of the second acquisition step on the basisof the auxiliary information acquired by the processing of the firstacquisition step; a modulation step of modulating the main dataencrypted by the processing of the encryption step; and a recording stepof recording the main data modulated by the processing of the modulationstep into a data area on the disc recording medium.

[0029] A program on a second recording medium according to the presentinvention is adapted for an information recording device for recordingmain data onto a disc recording medium having a data area for recordingthe main data and a burst cutting area for recording auxiliaryinformation, the program comprising: a first acquisition step ofacquiring the auxiliary information proper to the disc recording mediumrecorded in the burst cutting area, the auxiliary information beingblocked to generate error correction blocks with a header added thereto,the header containing an identification number and a block number; asecond acquisition step of acquiring the main data; an encryption stepof encrypting the main data acquired by the processing of the secondacquisition step on the basis of the auxiliary information acquired bythe processing of the first acquisition step; a modulation step ofmodulating the main data encrypted by the processing of the encryptionstep; and a recording step of recording the main data modulated by theprocessing of the modulation step into the data area on the discrecording medium.

[0030] A second program according to the present invention is executableby a computer which controls an information recording device forrecording main data onto a disc recording medium having a data area forrecording the main data and a burst cutting area for recording auxiliaryinformation, the program comprising: a first acquisition step ofacquiring the auxiliary information proper to the disc recording mediumrecorded in the burst cutting area, the auxiliary information beingblocked to generate error correction blocks with a header added thereto,the header containing an identification number and a block number; asecond acquisition step of acquiring the main data; an encryption stepof encrypting the main data acquired by the processing of the secondacquisition step on the basis of the auxiliary information acquired bythe processing of the first acquisition step; a modulation step ofmodulating the main data encrypted by the processing of the encryptionstep; and a recording step of recording the main data modulated by theprocessing of the modulation step into the data area on the discrecording medium.

[0031] An information reproducing device according to the presentinvention comprises: acquisition means for acquiring auxiliaryinformation proper to a disc recording medium recorded in a burstcutting area, the auxiliary information being blocked to generate errorcorrection blocks with a header added thereto, the header containing anidentification number and a block number; reproduction means forreproducing main data from a data area; demodulation means fordemodulating the main data reproduced by the reproduction means; anddecoding means for decoding the main data demodulated by thedemodulation means on the basis of the auxiliary information acquired bythe acquisition means.

[0032] Only a part of parities having a length of k−1 of the auxiliaryinformation may be encoded.

[0033] Only parities of (k−1)/2, which are a part of parities having alength of k−1, of the auxiliary information may be encoded.

[0034] The error correcting code RS(m,n,k) may be RS(248, 216, 33).

[0035] If the plurality of error correction blocks are recorded on thedisc recording medium, the acquisition means may select a predeterminederror correction block on the basis of the identification number and theblock number recorded in the header and may acquire the auxiliaryinformation of the selected error correction block.

[0036] If an error of the selected error correction block of theplurality of error correction blocks cannot be corrected, theacquisition means may select another error correction block having thecorresponding identification number and block number.

[0037] An information reproducing method according to the presentinvention comprises: an acquisition step of acquiring auxiliaryinformation proper to a disc recording medium recorded in a burstcutting area, the auxiliary information being blocked to generate errorcorrection blocks with a header added thereto, the header containing anidentification number and a block number; a reproduction step ofreproducing main data from a data area; a demodulation step ofdemodulating the main data reproduced by the processing of thereproduction step; and a decoding step of decoding the main datademodulated by the processing of the demodulation step on the basis ofthe auxiliary information acquired by the processing of the acquisitionstep.

[0038] A program on a third recording medium according to the presentinvention is adapted for an information reproducing device forreproducing main data from a disc recording medium having a data areafor recording the main data and a burst cutting area for recordingauxiliary information, the program comprising: an acquisition step ofacquiring the auxiliary information proper to the disc recording mediumrecorded in the burst cutting area, the auxiliary information beingblocked to generate error correction blocks with a header added thereto,the header containing an identification number and a block number; areproduction step of reproducing the main data from the data area; ademodulation step of demodulating the main data reproduced by theprocessing of the reproduction step; and a decoding step of decoding themain data demodulated by the processing of the demodulation step on thebasis of the auxiliary information acquired by the processing of theacquisition step.

[0039] A third program according to the present invention is executableby a computer which controls an information reproducing device forreproducing main data from a disc recording medium having a data areafor recording the main data and a burst cutting area for recordingauxiliary information, the program comprising: an acquisition step ofacquiring the auxiliary information proper to the disc recording mediumrecorded in the burst cutting area, the auxiliary information beingblocked to generate error correction blocks with a header added thereto,the header containing an identification number and a block number; areproduction step of reproducing the main data from the data area; ademodulation step of demodulating the main data reproduced by theprocessing of the reproduction step; and a decoding step of decoding themain data demodulated by the processing of the demodulation step on thebasis of the auxiliary information acquired by the processing of theacquisition step.

[0040] In the first information recording device and method, recordingmedium and program according to the present invention, auxiliaryinformation is blocked to generate error correction blocks with a headeradded thereto, the header containing an identification number and ablock number, and the auxiliary information is recorded in the burstcutting area.

[0041] The disc recording medium according to the present invention hasrecorded in its burst cutting area, auxiliary information blocked togenerate error correction blocks with a header added thereto, the headercontaining an identification number and a block number.

[0042] In the second information recording device and method, recordingmedium and program according to the present invention, auxiliaryinformation blocked to generate error correction blocks with a headeradded thereto, the header containing an identification number and ablock number, is acquired and main data is encrypted on the basis of theauxiliary information.

[0043] In the information reproducing device and method, recordingmedium and program according to the present invention, main data isdecoded on the basis of auxiliary information recorded in a burstcutting area and blocked to generate error correction blocks with aheader added thereto, the header containing an identification number anda block number.

BRIEF DESCRIPTION OF THE DRAWINGS

[0044]FIG. 1 shows a disc format of an optical disc to which the presentinvention is applied.

[0045]FIG. 2 illustrates 4/1 modulation.

[0046]FIG. 3 illustrates the relation between a channel and a mark.

[0047]FIG. 4 illustrates the structure of BCA data.

[0048]FIG. 5 shows an example of frame sync.

[0049]FIG. 6 illustrates the structure of an ECC block in a burstcutting area.

[0050]FIG. 7 illustrates the structure of an ECC block in a data area.

[0051]FIG. 8 illustrates a recording format of a BCA code.

[0052]FIG. 9 illustrates a BCA content code.

[0053]FIG. 10 shows the relation between a bit error rate of raw dataand an error rate of a BCA code.

[0054]FIG. 11 illustrates the structure of an ECC block of 64 kilobytesin the data area.

[0055]FIG. 12 shows the relation between a raw symbol error rate and acorrected symbol error rate.

[0056]FIG. 13 shows another structure of the ECC block.

[0057]FIG. 14 is a block diagram showing the structure of a discrecording device for recording a BCA code into the burst cutting area.

[0058]FIG. 15 is a flowchart for explaining BCA recording processing atthe disc recording device of FIG. 14.

[0059]FIG. 16 is a block diagram showing the structure of a discrecording/reproducing device to which the present invention is applied.

[0060]FIG. 17 is a flowchart for explaining data recording processing atthe disc recording/reproducing device of FIG. 16.

[0061]FIG. 18 is a flowchart for explaining the details of BCAreproduction processing at step S31 of FIG. 17.

[0062]FIG. 19 is a flowchart for explaining data reproduction processingat the disc recording/reproducing device of FIG. 16.

BEST MODE FOR CARRYING OUT THE INVENTION

[0063] An embodiment of the present invention will now be described withreference to the drawings.

[0064] An embodiment of the disc recording medium according to thepresent invention is a next-generation optical disc which can realize alarge capacity of more than 23.3 gigabytes with a diameter of 120 mm.With respect to this next-generation optical disc, a recording layer isformed on a substrate, and a transparent cover layer with a thickness of0.1 mm is formed on the recording layer. For recording and reproducingcontent data, for example, a blue-violet laser beam with a wavelength of405 nm is condensed by an optical pickup with a numerical aperture setat NA=0.85 and is cast onto the recording layer via the transparentcover layer having a thickness of 0.1 mm.

[0065]FIG. 1 shows the disc format of an optical disc 1 to which thepresent invention is applied. A burst cutting area (BCA) 1A isconcentrically formed in a range from a radium of 21.3 mm to a radius of22.0 mm on the outer side (in this example, on the inner side) of a dataarea 1B where content data (such as AV data) is recorded, on the innercircle of the optical disc 1. In this BCA, auxiliary informationincluding attribute information such as disc ID information proper tothe disc is recorded over 4648 channels, of 4750 channels (channel bits)per circle.

[0066]FIG. 2 shows a modulation method for data recorded in the burstcutting area 1A. In this example, source data of 2 bits is modulated tomodulation data of 7 bits. The modulation data of 7 bits is made up of asynchronizing part of 3 bits followed by a data part of 4 bits.

[0067] The synchronizing part has bits “010”. In the data part, one ofthe 4 bits is set to “1”. In the example of FIG. 2, the data part ofsource data “00” is set to “1000”. The data part of source data “01” isset to “0100”. The data part of source data “10” is set to “0010”. Andthe data part of source data “11” is set to “0001”.

[0068] Thus, in this modulation method, one of four channel bits isselected. Hereinafter, this modulation method is referred to as 4/1modulation.

[0069]FIG. 3 schematically shows the state where a synchronizing partand a data part are recorded in the burst cutting area 1A. The length L1(in the circumferential direction of the disc) of one channel bit isapproximately 30 μm. On the other hand, in a channel bit for which “1”is recorded, a mark with a length L2 of approximately 10 to 15 μm isrecorded. This mark is not formed in a channel of “0”, which is simply aspace.

[0070] In the example of FIG. 3, data having channel bits of “0101000”(data having channels bits corresponding to the source data “00” in FIG.2) is presented.

[0071]FIG. 4 shows the data structure of the data recorded in the burstcutting area 1A. As shown in FIG. 4, each frame (line) is made up of 5bytes. The leading 1 byte of each frame is a frame sync and the 4 bytesfollowing the frame sync constitute data.

[0072] The frame sync of the first frame is set to SB_(BCA,-1) and thedata is a preamble. All the value of the preamble is 00h. Using thispreamble, a channel clock is generated by a PLL, which will be describedlater.

[0073] Since the frame sync SB_(BCA,-1) of the first frame has a uniquevalue, the start position of the BCA code can be detected by using thisframe sync. Alternatively, both the frame sync SB_(BCA,-1) and thesubsequent preamble can be detected as the start position of the BCAcode.

[0074] The second to 33^(rd) frames are sectioned by four frames each.As the data of the second to fifth frames, user data I_(0,0) to I_(0,15)of 16 bytes are arranged. In the subsequent sixth to ninth frames,parities C_(0,0) to C_(0,15) of 16 bytes corresponding to the user dataI_(0,0) to I_(0,15) of the second to fifth frames are arranged.

[0075] One ECC block is constituted on the basis of the user data of thesecond to fifth frames and the parity data of the sixth to ninth frames.

[0076] Similarly, user data I_(1,0) to I_(1,15) are arranged in the10^(th) to 13^(th) frames and parities C_(1,0) to C_(1,15) correspondingto the user data are arranged in the 14^(th) to 17^(th) frames. Userdata I_(2,0) to I_(2,15) are arranged in the 18^(th) to 21^(st) framesand corresponding parities C_(2,0) to C_(2,15) are arranged in the22^(nd) to 25^(th) frames. User data I_(3,0) to I_(3,15) are arranged inthe 26^(th) to 29^(th) frames and corresponding parities C_(3,0) toC_(3,15) are arranged in the 30^(th) to 33^(rd) frames.

[0077] The frame syncs of the second to fifth frames are set toSB_(BCA,0). The frame syncs of the sixth to ninth frames are set toSB_(BCA,1). The frame syncs of the 10^(th) to 13^(th) frames are set toSB_(BCA,2). The frame syncs of the 14^(th) to 17^(th) frames are set toSB_(BCA,3). The frame syncs of the 18^(th) to 21^(st) frames are set toSB_(BCA,4). The frame syncs of the 22^(nd) to 25^(th) frames are set toSB_(BCA,5). The frame syncs of the 26^(th) to 29^(th) frames are set toSB_(BCA,6). The frame syncs of the 30^(th) to 33^(rd) frames are set toSB_(BCA,7).

[0078] The frame sync of termination of the 34^(th) frame is set toSB_(BCA,-2). The 34^(th) frame has no data arranged therein and only hasthe frame sync.

[0079] The data of FIG. 4 represents data before being 4/1-modulated inaccordance with the modulation method of FIG. 2. The total quantity ofdata is 166 (=5×4×8+5+1) bytes. As a result of modulating the data of166 bytes by 4/1 modulation shown in FIG. 2, 4648 (=166×8×7/2) channelbits are provided (FIG. 1).

[0080]FIG. 5 shows a specific example of the frame syncs shown in FIG.4. The example shown in FIG. 5 represents the structure of channel bitsafter being 4/1-modulated.

[0081] A frame sync of 28 channel bits is made up of a sync body of 14channel bits and sync ID of 14 channel bits.

[0082] The sync body of 14 channel bits is made up of a sync body 1 of 7channel bits and a sync body 2 of 7 channel bits. The sync ID of 14channel bits is made up of sync ID 1 of 7 channel bits and sync ID 2 of7 channel bits.

[0083] The sync body has an out-of-rule pattern of 4/1 modulation.Specifically, as shown in FIG. 2, in the case of 4/1 modulation, thevalue of the synchronizing part is set to “010”. However, thesynchronizing part of the sync body 2 is not “010” but “001”. Therefore,it is possible to easily identify the frame sync from the data.

[0084] The sync body 1 of each frame sync is set to “010 0001” and thesync body 2 is set to “001 0100”.

[0085] On the other hand, the sync IDs of the respective frame syncshave different values, thus making it possible to identify the framesyncs from each other.

[0086] Specifically, in the example of FIG. 5, the sync ID ofSB_(BCA,-1) of the preamble and the sync ID of the frame syncSB_(BCA,-2) of the termination are set to “010 0001”. Therefore, thepreamble and the termination can be easily identified from the otherframes. Since the sync ID 2 of the preamble frame has a value “010 0001”and the sync ID 2 of the terminal frame has a value “010 0010”, thepreamble frame and the termination frame can be identified from eachother.

[0087] Moreover, the frame syncs of the other frames can be identifiedfrom one another because they have different values, as shown in FIG. 5.

[0088]FIG. 6 shows the structure of an ECC block of a BCA codeconstituted as shown in FIG. 4. Specifically, a Reed-Solomon code ofRS(248,216,33) is used as an ECC code. The code has a code length m of248 bytes (symbols), a data length n of 216 bytes (symbols) and adistance of 33 bytes-(symbols).

[0089] This ECC block of the BCA code is constituted similarly to an ECCblock of content data, which is main data recorded in the data area 1Bshown in FIG. 1.

[0090] Specifically, as the ECC block in the data area 1B, again, aReed-Solomon code of RS(248,216,33) is used, as shown in FIG. 7.

[0091] However, in the ECC block of the BCA code, the leading 200 bytes(symbols) of the data length n of 216 bytes are fixed data, and anarbitrary value such as FFh is used, as shown in FIG. 6. The 16 bytes(symbols) I₀ to I₁₅ after the fixed data are user data substantiallyconstituting the BCA data.

[0092] Although the BCA data is arranged at the trailing end of the 216bytes (symbols) in FIG. 6, it may be arranged at the leading end.

[0093] Using the fixed data of 200 bytes and the BCA data of 16 bytes,parities of 32 bytes are calculated. If the fixed data of 200 bytes doesnot exist, the parities of 32 bytes cannot be calculated. Since thefixed data of 200 bytes is thus used as the base for calculating theparity, it is not simply stuffing data.

[0094] Moreover, in the present invention, only the parities C₀ to C₁₅of the leading 16 bytes are recorded on the optical disc 1 and theparities of the remaining 16 bytes are not recorded.

[0095] Of the data of 216 bytes (symbols), the fixed data of 200 bytesis not recorded and only the BCA data of 16 bytes is recorded. Afterall, of the ECC block of 248 bytes, only the BCA data of 16 bytes andthe parities of 16 bytes, that is, a total of 32 bytes (symbols), arerecorded.

[0096] As a result, the error correction performance corresponds to theerror correction performance of RS(32,16,17).

[0097] In-decoding, the same value is used as it is for the fixed dataof 200 bytes. The unrecorded parities of 16 bytes are decoded as pointererasure. That is of the parities of 32 bytes, the parities of the latter16 bytes are processed as having been erased. Even if a half of theparities are erased, their positions are known and therefore theoriginal parities can be decoded.

[0098] By thus using the same RS(248, 216, 33) as the ECC of the maindata recorded in the data area 1B, very high error correction capabilitycan be realized for the BCA code in the burst cutting area 1A. Since ECCprocessing of the BCA code can be carried out by using the same hardwareas for the ECC of the main data in the data area 1B, simplification ofthe structure and reduction in cost can be realized. Moreover, since itsuffices to record only 32 symbols, the scanning density can beincreased in comparison with the case of recording all the 248 symbolsand the detection is made easier, thus improving the reliability. It isalso possible to record a large volume of data (disc ID).

[0099]FIG. 8 shows the structure of the ECC block of the BCA. As shownin FIG. 8, in the present invention, four ECC blocks are recorded in theburst cutting area 1A.

[0100] Data of 16 bytes of each ECC block is made up of a header ofleading 2 bytes followed by content data of 14 bytes. The header is madeup of a BCA content code of 1 byte and a content data length of 1 byte.

[0101] In the BCA content code, 6 bits from a leading bit 7 to a bit 2constitute application ID, and 2 bits, that is, the last bit 1 and a bit0, constitute the block number, as shown in FIG. 9.

[0102] The optical disc recording/reproducing device is capable ofrecording and reproducing data to and from only an optical disc providedwith the BCA code having application ID set in advance. For example,data necessary to protect content data (such as key information forencrypting/decrypting content data or disc ID) can be recorded to theBCA code having specific application ID.

[0103] The block number is one of four numbers “00”, “01”, “10” and“11”.

[0104] If the content data of every ECC block has 14 bytes or less,every ECC block has the block number “00”.

[0105] On the other hand, if the same content data is recorded, forexample, as the content data of each of the leading two ECC blocks ofthe four ECC blocks (that is, if the same content data having the sameapplication ID is double-written), each of the two ECC blocks has theblock number “00”. That is, in-case of recording the same content data,the block number of the two ECC blocks are the same number.

[0106] If content data having different application ID from theapplication ID of the first two ECC blocks is recorded consecutivelythroughout 24 bytes in the remaining (latter) two ECC blocks, the firstECC block of the latter two ECC blocks has the block number “00” and thesecond ECC block has the block number “01”. That is, in case ofrecording content data over a plurality of ECC blocks, the block numberof each ECC block is the serial number. Each of the latter two ECCblocks has a content data length with a value of 24 bytes (which is theactual length of the user data).

[0107] On contrary, if the same content data is double-written, each ofthe ECC blocks have a content data length of 14 bytes (fixed length).

[0108] If the content data is less than 14 bytes, stuffing data is addedand each ECC block has a content data size of 14 bytes (fixed length).

[0109] Since the application ID and the block number are thus recordedin each ECC block, it can be identified which ECC block has desired datastored therein and whether the content data is multiple-written orsingly written.

[0110] The BCA content code, the content data length and the contentdata (16 bytes) of the leading ECC block of FIG. 8 correspond to I_(0.0)to I_(0,15) (16 bytes) of the leading ECC block of FIG. 4. Similarly,the BCA content codes, the content data length and the content data ofthe second to fourth ECC blocks of FIG. 8 correspond to I₀ to I₁₅ of thesecond to fourth ECC blocks of FIG. 4, respectively.

[0111]FIG. 10 shows the error correction capability of the BCA code. InFIG. 10, a curve A represents the error rate in the case where the samedata is recorded in each of four ECC blocks (quadruple writing), and acurve B represents the error rate of an error generated in one of fourECC blocks in the case where different data are recorded in the four ECCblocks (single writing).

[0112] As the optical disc 1 with the cover layer having a thickness of0.1 mm is inserted in the cartridge and the degree of adherence of dustparticles is examined, the adherence of dust particles is found inapproximately 0.1% of the entire area. Thus, the error rate of the BCAcode with respect to the bit error rate of 0.1% (=1E-3=1×10−3) isapproximately 1.0×E-12 for the curve B, and a much smaller value for thecurve A.

[0113] In FIG. 10, the horizontal axis represents the bit error rate ofraw data and the vertical axis represents the error rate of the BCAcode.

[0114] The error correction block of main data (content data) such as AVdata recorded in the data area 1B is constituted by a 64-kilobyte unit,as shown in FIG. 11. By thus expanding the structure of the ECC block,the interleave length can be increased and higher resistance to bursterrors is provided.

[0115] In this case, the unit of recording and reproduction may be a2-kilobyte sector unit. While recording or-reproducing data with anerror correction block of a 64-kilobyte unit, a desired 2-kilobytesector is recorded or reproduced therefrom.

[0116] The error correcting code is RS(248,216,33) and one errorcorrection block is made up of 304 correcting codes.

[0117] If an error detecting code (EDC) of 4 bytes is added to data of 2kilobytes (=2048 bytes), the total quantity of data is 2052 bytes. Onthe assumption that one sector is made up of data of 2052 bytes, 322-kilobyte sectors can be formed in the error correction block of 64kilobytes as a unit. Therefore, the quantity of data of the errorcorrection block of 64 kilobytes is 65664 (=2052×32) bytes.

[0118] A curve A in FIG. 12 represents the block error rate of a64-kilobyte unit as shown in FIG. 11, and a curve B represents thesymbol error rate. In FIG. 12, the horizontal axis represents the rawsymbol error rate and the vertical axis represents the corrected symbolerror rate.

[0119] When the raw symbol error rate on the horizontal axis of FIG. 12is at a value of 4.0E-3, the value of the corrected symbol error rate isfound to be approximately 1.0E-16 from the curve B. This symbol errorrate of 1.0E-16 is a value which realizes an almost error-free state(where no errors occur). At this point, the block error rate of the64-kilobyte ECC block is approximately 7E-12.

[0120] The values of the error rate shown in the graph of FIG. 10 areclose to or sufficiently smaller than the value of the error raterepresented by the block error rate of the curve A in FIG. 12. That is,by carrying out the above-described ECC block processing, an error ratesubstantially equal to the error rate in the data area 1B can be alsorealized in the burst cutting area 1A.

[0121] While four ECC blocks are recorded in the burst cutting area 1Ain the above-described example, it may be conceivable to record one ECCblock, as shown in FIG. 13.

[0122] However, in the case where the number of ECC blocks is one, asshown in FIG. 13, multiple writing of disc ID and recording of differentdisc IDs cannot be performed. If there is no need to perform multiplewriting or recording of a plurality of disc IDs, the number of ECCblocks may be one.

[0123] Giving an example of recording the disc ID information, a discrecording device 11 for recording information in the burst cutting area1A and ultimately forming the optical disc 1 will now be described withreference-to FIG. 14.

[0124] In FIG. 14, the disc ID information inputted via an inputterminal IN is stored in a register 21. The register 21 is connectedwith an ECC (error correcting code) circuit 20. The ECC circuit 20generates an error correcting code of a format shown in FIGS. 4 and 8from the disc ID information stored in the register 21. The disc IDinformation which is error correcting coded by the ECC circuit 20 issupplied to a 4/1 modulating unit 22.

[0125] The 4/1 modulating unit 22 performs 4/1 modulation on the disc IDinformation read out from the register 21 in accordance with a clock(channel clock) inputted from a VCO (voltage-controlled oscillator) 33,the inserts a frame sync signal and the like to generate data to berecorded in the burst cutting area 1A of the optical disc 1, and outputsthe generated data to a laser 23.

[0126] The 4/1 modulation by the 4/1 modulating unit 22 is alreadydescribed with reference to FIG. 2.

[0127] The laser 23 is, for example, a YAG laser or the like and casts ahigh-output laser beam onto the optical disc 1 via a mirror 24 and anobjective lens 25. The objective lens 25 includes, for example, acylindrical lens and casts the incident laser beam onto the burstcutting area 1A of the optical disc 1. Thus, the reflection film of theoptical disc 1 is irreversibly changed and the disc ID information isrecorded thereon.

[0128] A spindle motor 27 rotates the optical disc 1 under the controlof a spindle servo control unit 28, and the spindle motor 27 causes anFG (frequency generator) signal generator to generate an FG signal as apulse every time the optical disc 1 (spindle motor 27) rotates by apredetermined angle and outputs the FG signal to the spindle servocontrol unit 28. The spindle servo control unit 28, under the control ofa controller 29, controls the spindle motor 27 so that the spindle motor27 rotates at a predetermined rotation speed, on the basis of the FGsignal inputted from the spindle motor 27. The spindle servo controlunit 28 also outputs the FG signal inputted from the spindle motor 27,to the controller 29 and a PC (phase comparator) 31.

[0129] The controller 29 controls the spindle servo control unit 28 inaccordance with an operation signal inputted from an operating unit, notshown, thus driving the spindle motor 27 and rotating the optical disc1. The controller 29 also generates a control signal for controlling thefrequency division ratio of a frequency divider 30 on the basis of theFG signal inputted from the spindle servo control unit 28 and outputsthe control signal to the frequency divider 30.

[0130] The frequency divider 30, the PC 31, a LPF (low-pass filter) 32and the VCO 33 constitute a PLL (phase-locked loop).

[0131] The frequency divider 30 divides the frequency of the clockoutputted from the VCO 33 to a value 1/N (frequency division ratio) seton the basis of the control signal inputted from the controller 29 andoutputs the clock to the PC 31. The PC 31 compares the phase of theclock inputted from the frequency divider 30,with the phase of the FGsignal inputted from the spindle servo control unit 28 and thusgenerates and outputs a phase difference signal to the LPF 32. The LPF32 removes a high-frequency component from the inputted signal andoutputs the resultant signal to the VCO 33. The VCO 33 changes the phase(frequency) of the clock to be oscillated and outputted, on the basis ofthe voltage applied to the control terminal (that is, the output fromthe LPF 32).

[0132] The clock outputted from the VCO 33 is inputted to the 4/1modulating unit 22 and also inputted to the frequency divider 30, andthe VCO 33 is controlled so that the phase difference between the outputof the frequency divider 30 and the FG signal outputted from the spindleservo control unit 28 is constant. Therefore, the output of the VCO 33is a signal synchronously oscillating with a frequency which is N timesthat of the FG signal. The 4/1 modulating unit 22 outputs to the laser23 the data of the format described above with reference to FIGS. 4 and8, in accordance with the clock inputted from the VCO 33.

[0133] The controller 29 is connected with a drive 34. On the drive 34,a magnetic disk 41, an optical disc 42, a magneto-optical disc 43 or asemiconductor memory 44 is appropriately loaded. The drive 34 reads out,for example, a necessary computer program and supplies it to thecontroller 29.

[0134] The operation of the disc recording device will now be describedwith reference the flowchart of FIG. 15. At step S11, the register 21acquires disc ID information from the input terminal IN and stores it.At step S12, the ECC circuit 20 codes the disc ID information for fourblocks by using RS(248,216,33), which is a Reed-Solomon code, asdescribed above with reference to FIGS. 4 and 8. The ECC circuit 20calculates parities at step S13 and forms ECC blocks at step S14.Specifically, error correcting coding is performed on the disc IDinformation by using a code which uses RS(248,216,33) per block and hasa long distance 33 with respect to the number of data 216, that is, along distance code (LDC). Coding is performed with an inter-symboldistance which is achieved by increasing the proportion of the number ofparities to the number of data and thus improving the error correctioncapability. Moreover, since the above-described RS(248,216,33) ismultiple-written for four blocks at the most, the error correctioncapability is improved further.

[0135] The disc ID information recorded in the burst cutting area 1A ofthe optical disc 1 relates to the entire data on the disc (for example,whether or not the encrypted content data recorded in the data area 1Bof the optical disc 1 may be decrypted and reproduced is determined). Tothis end, the disc ID information requires high reliability. Therefore,coding with high error correction capability must be performed on thedisc ID information, as described above. The error correction capabilityis equivalent to or higher than the error correction capability of errorcorrecting coding performed on the content data recorded in the dataarea 1B, as described above.

[0136] When the start of recording is commanded, the controller 29 atstep S15 controls the spindle servo control unit 28 to rotate thespindle motor 27 at a constant angular velocity (CAV). The spindle motor27 generates an FG signal corresponding to the rotation and supplies theFG signal to the spindle servo control unit 28. The spindle servocontrol unit 28 supplies the FG signal to the PC 31. .

[0137] At step S16, a channel clock is generated. Specifically, the PC31 compares the phases of two input signals with each other and suppliesa resultant phase different signal to the VCO 33 via the LPF 32. The VCO33 generates a channel clock having a phase and frequency correspondingthe signal (controlled voltage) supplied from the LPF 32. The clockoutputted from the VCO 33 is supplied to the frequency divider 30, wherethe clock is frequency-divided by a predetermined frequency divisionratio set via the controller 29 and the frequency-divided clock issupplied to the PC 31.

[0138] In the above-described manner, the VCO 33 performs PLL so as torealize synchronization with one rotation of the optical disc 1, andthus generates and outputs a channel clock having a frequency which is Ntimes the frequency of the FG signal from the spindle motor 27.

[0139] For example, if the frequency of the FG signal per rotation is 50and the value of the frequency division ratio 1/N at the frequencydivider 30 is 1/95, a channel clock having 1/4750 cycles, which is1/(50×95) of the time of one rotation of the spindle motor 27 (opticaldisc 1), is generated.

[0140] At step S17, the 4/1 modulating unit 22 performs 4/1 modulationon the disc ID information to which the error correcting code is addedby the ECC circuit 20, on the basis of the channel clock supplied fromthe VCO 33, and supplies the 4/1-modulated data to the laser 23. At stepS18, the laser 23 generates a laser beam on the basis of the data(recorded channel bits) supplied from the 4/1 modulating unit 22 andcasts the laser beam onto the optical disc 1 via the mirror 24 and theobjective lens 25. In this manner, at the time of shipment from theplant, the disc ID information is recorded, for example, concentrically,over a plurality of tracks in the burst cutting area 1A of the opticaldisc 1.

[0141] When the duty of the mark of the recorded channel bits is to belowered, for example, when only 10 μm of the channel bit length of 30 μmis to be used as the mark (FIG. 3), the VCO 33 is oscillated at afrequency which is three times that of the channel clock so that onlyone of three clocks equivalent to the channel bits may be used as themark.

[0142] In the burst cutting area 1A of the optical disc 1, the same discID information is entered for four blocks, as described above. By doingso, the information can be obtained even when one of the four blockscannot be read. In the case of quadruple writing, even when a large dustparticle is adhered over two codes (blocks), the other two blocks areavailable and therefore an error can be corrected. Alternatively,different disc ID information is recorded in two or more blocks. Bydoing so, it is possible to manage the same optical disc 1 by four typesof different applications at the maximum.

[0143]FIG. 16 is a block diagram showing the structure of a discrecording/reproducing device 60 for recording main data into the dataarea 1B of the optical disc 1 which has the disc ID information recordedin its burst cutting area 1A as described above, and for reproducing therecorded main data.

[0144] A CPU 61 controls each part of the disc recording/reproducingdevice 60 in accordance with an operation signal inputted from anoperating unit, not shown, in order to record main data into the dataarea 1B of the optical disc I and reproducing the recorded main data.When reproducing or recording data, the CPU 61 causes the disc IDinformation on the optical disc 1 held by a register 71 to be outputtedto a decryption processing unit 74 or an encryption processing unit 75,and generates and outputs a control signal for instructing rotation orstop of the optical disc 1 to a servo control unit 63.

[0145] The servo control unit 63 causes an optical pickup 64 to seeks apredetermined position on the optical disc 1 on the basis of the controlsignal inputted from-the CPU 61, and carries out tracking control andfocusing control of the optical pickup 64 on the basis of a trackingerror signal (TK) and a focusing error signal (FS) supplied from amatrix amplifier (MA) 65. A spindle motor 62 rotates the optical disc 1at a predetermined rotation speed under the control of the servo controlunit 63.

[0146] In reproducing the disc ID information, the servo control unit 63rotates the optical disc 1 in accordance with the CAV (constant angularvelocity) mode. In recording and reproducing the main data, the servocontrol unit 63 rotates the optical disc 1 in accordance with the CLV(constant linear velocity) mode.

[0147] The optical pickup 64 is held by a predetermined thread mechanismso that is movable in the radial direction of the optical disc 1. Whenthe data recorded on the optical disc 1 is to be recorded, the opticalpickup 64 casts a laser beam onto the optical disc 1 in accordance witha control signal inputted from the servo control unit 63, then receivesits reflected beam, converts it to an electric signal, and outputs thesignal to the matrix amplifier 65. When new data is to be recorded ontothe optical disc 1, the optical pickup 64 casts a laser beam onto theoptical disc 1 on the basis of data outputted from a modulating unit 77and causes the data to be recorded in the data area 1B of the opticaldisc 1.

[0148] The matrix amplifier 65 processes the signal inputted from theoptical pickup 64 and outputs a reproduced signal of the datacorresponding to the disc ID information recorded in the burst cuttingarea 1A to a LPF 66. The matrix amplifier 65 also generates a trackingerror signal with its signal level changed in accordance with thequantity of tracking errors and a focusing error signal with its signallevel changed in accordance with the quantity of focusing errors, thenoutputs the tracking error signal and the focusing error signal to theservo control unit 63, and outputs a reproduced signal of the datarecorded in the data area 1B to-a demodulating unit 72.

[0149] The LPF 66 restrains the variance in the reproduced signal due tonoise by removing a high-frequency component from the inputted signaland outputs the resultant signal to a comparator 67. The comparator 67compares the inputted signal with a predetermined level, therebybinarizing the signal. A demodulating unit 68 samples the inputtedsignal on the basis of a sampling clock inputted from a crystaloscillator 69, performs channel position correction and demodulation (inthis case, 4/1 demodulation) on the signal, and outputs the resultantsignal to an ECC unit 70. The number of sampling clocks is a numericalvalue based on the disc ID recording format. The ECC unit 70 performserror correction processing on the inputted demodulated data (disc IDinformation) on the basis of the error correcting code (RS(248,216,33))contained in the disc ID information and causes the register 71 to storethe error-corrected disc ID information. The ECC unit 70 and an ECC unit73, which will be described later, may be a single common ECC unit.

[0150] Meanwhile, the demodulating unit 72 demodulates the data (contentdata) supplied from the matrix amplifier 65 and supplies the demodulateddata to the ECC unit 73. The ECC unit 73 performs error correction onthe inputted demodulated data (for example, coded by RS(248,216,33)) byusing 32 parities and then supplies the error-corrected data to thedecryption processing unit 74. The decryption processing unit 74decrypts the content data supplied from the ECC unit 73 on the basis ofthe disc ID information supplied from the register 71 and outputs thedecrypted data to a device, not shown.

[0151] The encryption processing unit 75 encrypts content data inputtedfor recording on the basis of the disc ID information supplied from theregister 71 and outputs the encrypted data to an ECC unit 76. The ECCunit 76 codes the inputted encrypted data by using RS(248,216,33) andoutputs the coded data to the modulating unit 77.

[0152] In a drive 81, a magnetic disc 91, an optical disc 92, amagneto-optical disc 93 or a semiconductor memory 94 is loaded, whennecessary. The drive 81 supplies a program read out from the medium tothe CPU 61.

[0153] The operation in data recording will now be described withreference to FIG. 17. When the optical disc 1 is loaded in the discrecording/reproducing device, the CPU 61 executes BCA reproductionprocessing at step S31. This BCA reproduction processing is described indetail in FIG. 18.

[0154] Specifically, at step S51, the CPU 61 controls the servo controlunit 63 to rotate the spindle motor 62 at a constant angular velocity(in accordance with the CAV mode). The velocity is the same as thevelocity in the case where the spindle motor 27 of the disc recordingdevice of FIG. 14 rotates the optical disc 1.

[0155] At step S52, the servo control unit 62 moves the optical pickup64 in the radial direction of the optical disc 1 and causes the opticalpickup 64 to reproduce the data in the burst cutting area 1A of theoptical disc 1.

[0156] At step S53, demodulation processing is carried out.Specifically, the reproduced data outputted from the optical pickup 64is inputted to the comparator 67 via the matrix amplifier 65 and the LPF66 and is binarized there. The demodulating unit 68 samples the binarydata inputted from the comparator 67 on the basis of the sampling clocksupplied from the crystal oscillator 66 and demodulates the binary data.The demodulating unit 68 also carries out processing to correct thechannel bits and word. The demodulated data of four blocks outputtedfrom the demodulating unit 68 is supplied to the ECC unit 70.

[0157] At step S54, the ECC unit 70 performs error correction processingon the demodulated data of four blocks in total. Specifically, the ECCunit 70 executes-ECC decoding processing by using the fixed data of 200bytes described with reference to FIG. 6 for each block, and by usingpointer erasure processing on the assumption that the parities of thelatter 16 bytes of the parities of 32 bytes have been erased.

[0158] At step S55, the CPU 61 reads the header of the block on whicherror correction processing has been performed by the ECC unit 70. Asdescribed above with reference to FIG. 8, application ID of 6 bits isstored as BCA content data in the header. The CPU 61 extracts theapplication ID from -the header, and at step S56, determines whether ornot this application ID is available to the CPU 61 itself. If it isdetermined that the application ID thus read is not available to the CPU61 itself, the CPU 61 cannot record data to or reproduce data from theoptical disc 1. Therefore, the CPU 61 goes to step S62 and executeserror processing. For example, the CPU 61 causes a display unit, notshown, to display a message like “this disc cannot be used.”

[0159] If it is determined at step S56 that the application ID isavailable, the CPU 61 goes to step S57 and selects a block having theavailable application ID from the four blocks.

[0160] At step S58, the CPU 61 determines whether or not the disc ID hasbeen multiple-written from the application ID and the block number. Ifthe disc ID has been multiple-written, the CPU 61 goes to step S59 andselects one of the blocks in which multiple writing has been carriedout. For example, if error correction cannot be carried out in the blockselected by the processing of step S57, the CPU 61 selects another blockin which multiple writing has been carried out (another block which hasa header with the same (corresponding) application ID and block numberrecorded therein and can be error-corrected). If it is determined atstep S58 that disc ID has not been multiple-written, the processing ofstep S59 is skipped. That is, in this case, the block selected at stepS57 is the only block to be selected as the reading object.

[0161] Next, at step S60, the CPU 61 extracts the disc ID of the blockselected by the processing of step S57 or step S59. Specifically, thedisc ID is made up of the content data of FIG. 8. Having extracted thedisc ID, the CPU 61 at step S62 controls the ECC unit 70 to store thedisc ID in the register 71.

[0162] In this manner, if the loaded optical disc can be used, the discID information recorded in the burst cutting area 1A of the optical disc1 is error-corrected and stored in the register 71.

[0163] Referring again to FIG. 17, at step S32, the CPU 61 controls theservo control unit 63 to rotate the optical disc 1 via the spindle motor62 in accordance with the CLV mode. At step S33, the encryptionprocessing unit 75 reads the disc ID information stored in the register71.

[0164] At step S34, the encryption processing unit 75 encrypts contentdata for recording inputted from a device, not shown, on the basis ofthe disc ID information read from the register 71, and outputs theencrypted content data to the ECC unit 76. At step S35, the ECC unit 76codes the content data inputted from the encryption processing unit 75by using RS(248,216,33) and outputs the coded content data to themodulating unit 77. At step S36, the modulating unit 77 modulates thecoded content data inputted from the ECC unit 76 in accordance with apredetermined modulation mode and outputs the modulated content data-tothe optical pickup 64. At step S37, the optical pickup 64 records thecontent data inputted from the modulating unit 77 into the data area 1Bof the optical disc 1.

[0165] The processing for reproducing content data will now be describedwith reference to the flowchart of FIG. 19.

[0166] First, at step S81, the BCA reproduction processing is executed.This processing similar to the-processing shown in FIG. 18.

[0167] If the disc ID of the corresponding application ID is alreadystored in the register 71, this BCA reproduction processing can beomitted. However, if the application ID differs, the BCA reproductionprocessing is executed again.

[0168] The processing goes to step S82 and the CPU 61 executes theprocessing to reproduce data from the data area 1B.

[0169] Specifically, the CPU 61 controls the servo control unit 63 torotate the optical disc 1 in accordance with the CLV mode similarly tothe above-described case. The optical pickup 64 reproduces data in thedata area 1B of the optical disc 1 and outputs the reproduced data tothe matrix amplifier 65. The matrix amplifier 65 supplies the reproduceddata to the demodulating unit 72.

[0170] At step S83, the demodulating unit 72 demodulates the reproducedcontent data inputted thereto in accordance with a demodulation modecorresponding to the modulation mode at the modulating unit 77, andoutputs the demodulated data to the ECC unit 73. At step S84, the ECCunit 73 performs error correction processing on the demodulated datainputted from the demodulating unit 72 by using RS(248,216,33) asdescribed above and then supplies the error-corrected data to thedecryption processing unit 74. The decryption processing unit 74, atstep S85, reads the disc ID stored in the register 71, and at step S86,decodes the content data (encrypted content data) inputted from the ECCunit 73 on the basis of the disc ID information read from the register71 and outputs the decoded data to a device, not shown.

[0171] The content data is encrypted and then recorded in the data area1B of the optical disc 1 as described above. Even when the encryptedcontent data is directly copied to another disc by a computer or thelike, the disc ID information cannot be copied and the content datacannot be decrypted. Therefore, unauthorized copying of a large quantityof data can be substantially restrained.

[0172] In reproducing the disc ID information, it is assumed that thereproducing operation is carried out without performing tracking servo.Therefore, if the reproducing operation is carried out repeatedly over aplurality rotations of the optical disc 1, the radial position might beslightly shifted, generating different results of reproduction(reproduced data). Thus, the reproducing operation or correctingoperation can be carried out over a plurality of rotations.

[0173] While disc ID is recorded as content data in the abovedescription, auxiliary data other than disc ID may be recorded.

[0174] The present invention may also be applied to CD (compact disc),MD (mini disc: trade name by Sony Corporation) and DVD (digitalversatile disc) as well as the above-described optical disc.

[0175] The above-described series of processing can also be executed bysoftware. The software may be installed from a recording medium, forexample, to a general-purpose personal computer which is capable ofexecuting various functions, by installing a program constituting thatsoftware into a computer embedded in dedicated hardware, or byinstalling various programs.

[0176] The recording medium is constituted by a package medium such asthe magnetic disk 41, 91 (including a flexible disk), the optical disc42, 92 (including CD-ROM (compact disc-read only memory), DVD (digitalversatile disc)), the magneto-optical disc 43, 93 (including so-calledMD (mini disc: trade name by Sony Corporation)) or the semiconductormemory 44, 94, on which the program is recorded and which is distributedfor providing the program to a user, separately from the computer, asshown in FIG. 14 or FIG. 16.

[0177] In this specification, the steps describing the program recordedon the recording medium include the processing which is not necessarilycarried out in time series but is executed in parallel or individually,as well as the processing carried out in time series in accordance withthe described order.

[0178] Moreover, in this specification, the system refers to a wholedevice constituted by a plurality of devices.

[0179] While the invention has been described in accordance with certainpreferred embodiments thereof illustrated in the accompanying drawingsand described in the above description in detail, it should beunderstood by those ordinarily skilled in the art that the invention isnot limited to the embodiments, but various modifications, alternativeconstructions or equivalents can be implemented without departing fromthe scope and spirit of the present invention as set forth and definedby the appended claims.

[0180] Industrial Applicability

[0181] According to the present invention, the same disc recordingmedium can be managed by a plurality of applications.

[0182] Each application can learn the structures of blocks and candetermine whether data of each block has been multiple-written or not.

[0183] In each block, data which is longer than the data part of theblock can be recorded.

1. An information recording device for recording auxiliary informationonto a disc recording medium having a data area for recording main dataand a burst cutting area for recording the auxiliary information, thedevice comprising: acquisition means for acquiring the auxiliaryinformation; blocking means for appending a header containing anidentification number and a block number to the auxiliary informationacquired by the acquisition means, thus generating error correctionblocks each constituting a processing unit for error correction:recording means for recording the error correction blocks containing theauxiliary information having the header added thereto, which aregenerated by the blocking means, into the burst cutting area on the discrecording medium; and control means for performing control so that whenthe same said auxiliary information is arranged in each of plural saiderror correction blocks, the block numbers of the respective errorcorrection blocks are the same whereas when the auxiliary information isarranged over plural said error correction blocks, the block numbers ofthe respective error correction blocks are serial numbers.
 2. Canceled3. Canceled
 4. The information recording device as claimed in claim 1,wherein the blocking means causes the header to contain lengthinformation representing the length of the auxiliary information.
 5. Theinformation recording device as claimed in claim 1, wherein the blockingmeans causes the header to contain length information representing thelength of the auxiliary information, and when arranging the auxiliaryinformation over the plurality of error correction blocks, the blockingmeans describes the actual length of the auxiliary information as thelength information of each of the plurality of error correction blocksover which the auxiliary information is arranged.
 6. The informationrecording device as claimed in claim 1, wherein the blocking meanscauses the header to contain length information representing the lengthof the auxiliary information, and if the auxiliary information isshorter than a fixed-length data part of the error correction blocks,the blocking means describes the length of the data part of the errorcorrection blocks as the length information of the error correctionblocks.
 7. The information recording device as claimed in claim 1,further comprising modulation means for modulating the error correctionblocks generated by the blocking means, wherein the recording meansrecords the error correction blocks modulated by the modulation meansinto the burst cutting area on the disc recording medium.
 8. Theinformation recording device as claimed in claim 7, wherein the blockingmeans uses error correction blocks having an error correcting codeRS(m,n,k) as the error correction blocks.
 9. The information recordingdevice as claimed in claim 8, wherein the modulation means modulatesonly a part of parities having a length of k−1.
 10. The informationrecording device as claimed in claim 9, wherein the modulation meansmodulates only parities of (k−1)/2, which are a part of parities havinga length of k−1.
 11. The information recording device as claimed inclaim 7, wherein the modulation means 4/1-modulates the error correctionblocks.
 12. An information recording method for an information recordingdevice which records auxiliary information onto a disc recording mediumhaving a data area for recording main data and a burst cutting area forrecording the auxiliary information, the method comprising: anacquisition step of acquiring the auxiliary information; a blocking stepof appending a header containing an identification number and a blocknumber to the auxiliary information acquired by the processing of theacquisition step, thus generating error correction blocks eachconstituting a processing unit for error correction; a recording step ofrecording the plurality of error correction blocks containing theauxiliary information having the header added thereto, which aregenerated by the processing of the blocking step, into the burst cuttingarea on the disc recording medium, and a control step of performingcontrol so that when the same said auxiliary information is arranged ineach of plural said error correction blocks the block numbers of therespective error correction blocks are the same whereas when theauxiliary information is arranged over plural said error correctionblocks the block numbers of the respective error correction blocks areserial number.
 13. A recording medium having a computer-readable programrecorded thereon, the program being adapted for an information recordingdevice which records auxiliary data onto a disc recording medium havingdata area for recording main data and a burst cutting area for recordingthe auxiliary information, the program comprising: an acquisition stepof acquiring the auxiliary information; a blocking step of appending aheader containing an identification number and a block number to theauxiliary information acquired by the processing of the acquisitionsteps, thus generating error correction blocks each constituting aprocessing unit for error correction; a recording step of recordingerror correction blocks containing the auxiliary information having theheader added thereto, which are generated by the processing of theblocking step, into the burst cutting area on the disc recording medium;and a control step of performing control so that when the same saidauxiliary information is arranged in each of plural said errorcorrection blocks, the block numbers of the respective error correctionblocks are the same, whereas when the auxiliary information is arrangedover plural said error correction blocks, the block numbers of therespective error correction blocks are serial numbers.
 14. A programexecutable by a computer which controls an information recording devicefor recording auxiliary information onto a disc recording medium havinga data area for recording main data and a burst cutting area forrecording the auxiliary information, the program comprising: anacquisition step of acquiring the auxiliary information; a blocking stepof appending a header containing an identification number and a blocknumber to the auxiliary information acquired by the processing of theacquisition step, thus generating error correction blocks eachconstituting a processing unit for error correction, a recording step ofrecording the error correction blocks containing the auxiliaryinformation having the header added thereto, which are generated by theprocessing of the blocking step, into the burst cutting area on the discrecording medium; and a control step of performing control so that whenthe same said auxiliary information is arranged in each of plural saiderror correction blocks, the block numbers of the respective errorcorrection blocks are the same, whereas when the auxiliary informationis arranged over plural said error correction blocks, the block numbersof the respective error correction blocks are serial numbers.
 15. A discrecording medium having a data area for recording main data and a burstcutting area for recording auxiliary information, wherein errorcorrection blocks generated by appending a header containing anidentification number and a block number to the auxiliary informationare recorded in the burst cutting area, and when the same said auxiliaryinformation is arranged in each of plural said error correction blocksthe block numbers of the respective error correction blocks are thesame, whereas when the auxiliary information is arranged over pluralsaid error correction blocks, the block numbers of the respective errorcorrection blocks are serial numbers.
 16. An information recordingdevice for recording main data onto a disc recording medium having adata area for recording the main data and a burst cutting area forrecording auxiliary information, the device comprising: firstacquisition means for acquiring the auxiliary information recorded inthe burst cutting area, the auxiliary information being blocked togenerate error correction blocks with a header added thereto, the headercontaining an identification number and a block number; secondacquisition means for acquiring the main data; encryption means forencrypting the main data acquired by the second acquisition means on thebasis of the auxiliary information acquired by the first acquisitionmeans; modulation means for modulating the main data encrypted by theencryption means; and recording means for recording the main datamodulated by the modulation means into the data area on the discrecording medium.
 17. The information recording device as claimed inclaim 16, wherein only a part of parities having a length of k−1 of theauxiliary information is encoded.
 18. The information recording deviceas claimed in claim 17, wherein only parities of (k−1)/2, which are apart of parities having a length of k−1, of the auxiliary informationare encoded.
 19. The information recording device as claimed in claim16, wherein the error correcting code RS(m,n,k) is RS(248, 216, 33). 20.An information recording method for an information recording devicewhich records main data onto a disc recording medium having a data areafor recording the main data and a burst cutting area for recordingauxiliary information, the method comprising: a first acquisition stepof acquiring the auxiliary information recorded in the burst cuttingarea, the auxiliary information being blocked to generate errorcorrection blocks with a header added thereto, the header containing anidentification number and a block number; a second acquisition step ofacquiring the main data; an encryption step of encrypting the main dataacquired by the processing of the second acquisition step on the basisof the auxiliary information acquired by the processing of the firstacquisition step; a modulation step of modulating the main dataencrypted by the processing of the encryption step; and a recording stepof recording the main data modulated by the processing of the modulationstep into the data area on the disc recording medium.
 21. A recordingmedium having a computer-readable program recorded thereon, the programbeing adapted for an information recording device which record main dataonto a disc recording medium having a data area for recording the maindata and a burst cutting area for recording auxiliary information, theprogram comprising: a first acquisition step of acquiring the auxiliaryinformation recorded in the burst cutting area, the auxiliaryinformation being blocked to generate error correction blocks with aheader added thereto, the header containing an identification number anda block number; a second acquisition step of acquiring the main data; anencryption step of encrypting the main data acquired by the processingof the second acquisition step on the basis of the auxiliary informationacquired by the processing of the first acquisition step; a modulationstep of modulating the main data encrypted by the processing of theencryption step; and a recording step of recording the main datamodulated by the processing of the modulation step into the data area onthe disc recording medium.
 22. A program executable by a computer whichcontrols an information recording device for recording main data onto adisc recording medium having a data area for recording the main data anda burst cutting area for recording auxiliary information, the programcomprising: a first acquisition step of acquiring the auxiliaryinformation recorded in the burst cutting area, the auxiliaryinformation being blocked to generate error correction blocks with aheader added thereto, the header containing an identification number anda block number; a second acquisition step of acquiring the main data; anencryption step of encrypting the main data acquired by the processingof the second acquisition step on the basis of the auxiliary informationacquired by the processing of the first acquisition step; a modulationstep of modulating the main data encrypted by the processing of theencryption step; and a recording step of recording the main datamodulated by the processing of the modulation step into the data area onthe disc recording medium.
 23. An information reproducing device forreproducing main data from a disc recording medium having a data area inwhich the main data is recorded and a burst cutting area in whichauxiliary information is recorded as error correction blocks each havinga header added thereto, the header containing an identification numberand a block number, the device comprising: acquisition means foracquiring the auxiliary information recorded in the burst cutting area;reproduction means for reproducing the main data from the data area;demodulation means for demodulating the main data reproduced by thereproduction means; decoding means for decoding the main datademodulated by the demodulation means on the basis of the auxiliaryinformation acquired by the acquisition means; and judging means forjudging that the same said auxiliary information is arranged in each ofplural said error correction blocks when the block numbers of therespective error correction blocks are the same, and fudging that theauxiliary information is arranged over plural said error correctionblocks when the block numbers of the respective error correction blocksare serial numbers.
 24. The information reproducing device as claimed inclaim 23, wherein only a part of parities having a length of k−1 of theauxiliary information is encoded.
 25. The information reproducing deviceas claimed in claim 24, wherein only parities of (k−1)/2, which are apart of parities having a length of k−1, of the auxiliary informationare encoded.
 26. The information reproducing device as claimed in claim23, wherein the error correcting code RS(m,n,k) is RS(248, 216, 33). 27.The information reproducing device as claimed in claim 23, wherein ifthe plurality of error correction blocks are recorded on the discrecording medium, the acquisition means selects a predetermined errorcorrection block on the basis of the identification number and the blocknumber recorded in the header and acquires the auxiliary information ofthe selected error correction block.
 28. The information reproducingdevice as claimed in claim 27, wherein if an error of the selected errorcorrection block of the plurality of error correction blocks cannot becorrected, the acquisition means selects another error correction blockhaving the corresponding identification number and block number.
 29. Aninformation reproducing method for an information reproducing devicewhich reproduces main data from a disc recording medium having a dataarea in which the main data and a burst cutting area in which auxiliaryinformation is recorded as error correction blocks each having a headeradded thereto, the header containing an identification number and ablock number, the method comprising: an acquisition step of acquiringthe auxiliary information recorded in the burst cutting area; areproduction step of reproducing the main data from the data area; ademodulation step of demodulating the main data reproduced by theprocessing of the reproduction step; a decoding step of decoding themain data demodulated by the processing of the demodulation step on thebasis of the auxiliary information acquired by the processing of theacquisition step; and a judging step of judging that the same saidauxiliary information is arranged in each of plural said errorcorrection blocks when the block numbers of the respective errorcorrection blocks are the same, and judging that the auxiliaryinformation is arranged over plural said error correction blocks whenthe block numbers of the respective error correction blocks are serialnumbers.
 30. A recording medium having a computer-readable programrecorded thereon, the program being adapted for an informationreproducing device which reproduces main data from a disc recordingmedium having a data area in which the main data is recorded and a burstcutting area in which auxiliary information is recorded as errorcorrection blocks each having a header added thereto, the headercontaining an identification number and a block number, the programcomprising: an acquisition step of acquiring the auxiliary informationrecorded in the burst cutting area; a reproduction step of reproducingthe main data from the data area; a demodulation step of demodulatingthe main data reproduced by the processing of the reproduction step; adecoding step of decoding the main data demodulated by the processing ofthe demodulation step on the basis of the auxiliary information acquiredby the processing of the acquisition step; and a judging step of judgingthat the same said auxiliary information is arranged in each of pluralsaid error correction blocks when the block numbers of the respectiveerror correction blocks are the same and judging that the auxiliaryinformation is arranged over plural said error correction blocks whenthe block numbers of the respective error correction blocks are serialnumbers.
 31. A program executable by a computer which controls aninformation reproducing device for reproducing main data from a discrecording medium having a data area for recording the main data isrecorded and a burst cutting area in which auxiliary information isrecorded as error correction blocks each having a header added thereto,the header containing an identification number and a block number, theprogram comprising: an acquisition step of acquiring the auxiliaryinformation recorded in the burst cutting area; a reproduction step ofreproducing the main data from the data area; a demodulation step ofdemodulating the main data reproduced by the processing of thereproduction step; a decoding step of decoding the main data demodulatedby the processing of the demodulation step on the basis of the auxiliaryinformation acquired by the processing of the acquisition step; and ajudging step of judging that the same said auxiliary information isarranged in each of plural said error correction blocks when the blocknumbers of the respective error correction blocks are the same, andjudging that the auxiliary information is arranged over plural saiderror correction blocks when the block numbers of the respective errorcorrection blocks are serial numbers.